topic Re: How model lot size constraint in Proc MIRP in Mathematical Optimization, Discrete-Event Simulation, and OR

How model lot size constraint in Proc MIRP

lokendra_devangan_corecompete_com — Mon, 20 Feb 2017 10:53:57 GMT

Dear Sir/Madam,

I am using proc MIRP for modeling a supply chain network. I can see in Proc IRP there is lotsize keyword in replenishment statement but not in Proc MIRP.

How can I model lotsize in MIRP?

How can I model order cycle in MIRP?

Thanking in advance.

Lokendra

Re: How model lot size constraint in Proc MIRP

KDuck — Mon, 20 Feb 2017 16:53:13 GMT

Hello Lokendra,

For modeling the lotsize, you can use the variable of BATCHSIZE in the NODEDATA=dataset.

For the order cycle, you can use the variable of PBR in the NODEDATA=dataset. PBR specifies the number of periods between

two replenishment orders. Its default value is 1.

Thanks,

KDuck

Re: How model lot size constraint in Proc MIRP

lokendra_devangan_corecompete_com — Fri, 03 Mar 2017 10:11:25 GMT

Thanks.

Whenever I am using OBJECTIVE=POLICY_ORDER_KPI and using Horizon=100 in the output I get different values for reorder level and OUTL. I intermittent demand model and have variance and mean but want to assume stationary demand. How to model this. This will be very helpful. When I do not use HOrizon option I get same reorder point and OUTL for 12 periods.

Also when we use OBJECTIVE=EVALISL I do not get reorder level in the output. How can I get. I am running this for different service level and want see the KPI change.

thanks in advance

Lokendra

Re: How model lot size constraint in Proc MIRP

KDuck — Wed, 08 Mar 2017 16:34:37 GMT

If you have run with the specified inventory, it is expected to get different values of reorder level. And the default value of Horizon option is 12.

To obtain the identical reorder level for the stationary demand, you may try to run the following steps:

Do the policy optimization by OBJECTIVE=OPTPOLICY without inventory data
Set the inventory data based on this policy
Estimate KPIs by OBJECTIVE=PREDICTKPI

If you still have some questions or issues, please provide us your code and data sets.

For your second question,

since SS policy is used for OBJECTIVE=EVALISL, you can simply compute the reorder level as (order upto level – 1).

Thanks,

KDuck

Re: How model lot size constraint in Proc MIRP

lokendra_devangan_corecompete_com — Fri, 10 Mar 2017 08:02:14 GMT

Thank You